Synchronizing mechanism



April 29, 1941.

J. H. GORDON, JR 2,239,710

SYNCHRONIZING MECHANISM Filed March 24, 195s Patented Apr. 29, 1941sYNoHnoNrzING ME'CHANISM James H. Gordon, Jr., Union, N. J., assigner toAmerican C'an Company, New York, N. Y., a corporation of New JerseyApplicata@ March 24, 1939, serial No. 264,016

- s claims. (ci. 19a-22) The present invention relates to asynchronizing mechanism and the like and has particular reference tomaintaining a predetermined timed relation between moving machine, partswhich are apt to become unsynchronized in their cycle of movement.

In certain types of machines it is extremely difficult to maintainmoving parts in their proper synchronism during their cycle ofoperations.

By way of example', one such machine may include a long metallic linkconveyor which is adapted to operate in synchronism with other.

moving parts such as a turret or the like for placing articles ofmanufacture on the conveyor in predetermined positions. When suchA aconveyor is subjected to temperature changes such asY passing throughovens or other heated sections of a machine it expands` and therebyresults in an elongation or stretching of the conveyo-r parts. It hasbeen found that such stretching alters the distance betweenpredetermined places or spaces on the conveyor which; places are adaptedto receive the articles'fed thereto. This stretching produces a changeof lineal speed of the conveyor past a predetermined point adjacent itspath rof travel and hence throws the conveyor out 'of synchronism withfeeding devices or other associated mechanism.

The present invention contemplates overcom-y ing this difficulty by ruseof a synchronizing mechanism which constantly operates in accordancewith the degree of stretch in the conveyor to adjust the speed of theassociated feeding devlces. 1

An object therefore of the invention is the provision of a synchronizingmechanism Which is adapted to maintain at all times a predeterminedtimed relation between the speeds of machine parts which move throughdifferent cycles but which cooperate with each otherr in the operationofthe machine.

Numerous other objects and advantages ofthe invention will be apparentas it is betterfunderstood from the following description, which, takenin connection with the accompanying drawing, discloses a preferredembodiment thereof.

Referring t0 the drawing: Figure 1 is a perspective view of a machinewhich includes a synchronizing mechanism embodying the instantinvention; and

Fig. 2 is a wiring diagram of certain electric apparatus used in themechanism. l

As a preferred embodiment o-fthe .invention the drawing illustrates acontainer or can han-Y dling machine in which filled cansfA (Fig. 1)

' oven D.

the machine.

from a suitable source of supply are received by a rotating turret B andare placed by the turret in predetermined positions on along movingendless conveyor C. The conveyor is disposed in a chamber D which ispreferably heated inany suitable manner for treating the can contents asthe cans are conveyed therethrough. This chamber is enclosed by a casingE which also supports most of the moving parts of the machine and servesas a main frame for the machine. At the discharge end of the conveyo-rthe treated cans may be removed therefrom in any suitable manner andthus discharged to a desired place 0f deposit. y

The cans A enter the machine b-y way of a runway II the machine end ofwhich is secured to a side Wall of the casing E. The cans are maintainedin single file or line by guide rails I2 which are secured to therunway.

The turret B is located at the end of the runway II and is partiallydisposed in an opening formed in the side wall of the casing E. Thisturret is provided with spaced pockets I3 which receive individual cansmoving along the runway and the turret propels them through the casingopening and into the chamber D. Inside the chamber the turret places thecans onto the conveyor C. The turret is mounted on the upper end of avertical shaft I4 carried in bearings I5 formed in a `gear casing I6adjacent the main frame E.

The shaft is rotated as will hereinafter be explained.

spaced and parallel endless chains I1 which are connected transverselyby cross-nights I8. These nights receive the cans A from the turret B.Each alternate flight is provided with a locating dog I9 which engagesbehind a can A placed thereon and holds the can in place While it iscarried by the moving conveyor through the The conveyor chains` Il takeover pairs of spaced driving sprockets 2I located at the discharge endof the machine and over idler sprockets 22 which are located at theopposite end of The driving sprockets 2I are mounted on a driving shaft23 journaled in bearings 24 formed on a frame extension 25 of the mainframe E. The driving shaft is rotated from any suitable source of power,such as` an electric motor or belt.

The idler sprockets 22 are loosely mounted on an idler shaft 2l whichextends through slots 2B formed in the main frame E. The ends of theidler shaft pro-ject beyond and outside of the main frame and carrysprockets 29 having chains 3| which pass over them. Oen end c-f eachchain is secured to a boss 32 formed on the main frame E. After passingover the sprockets 29 the chains extend over a second pair of sprockets33 carried on the outer ends of a cross shaft 34 mounted in bearingsformed in lugs 35 extended out from the end of the main frame. The outerends of the chains depend from the sprockets 33 and are connected to andsupport a weight bar Thus the weight bar 31 draws the weight chains 3|taut over the sprockets 29, 33 and hence pulls on the idler sprocketshaft 21. This holds the conveyor` chains I1 taut. With lthisconstruction any stretch occurring in the conveyor chains is immediatelytaken up by the weight bar and hence the conveyor is always maintainedin a taut condition.

'Ihe can feedin turret B hereinbefore mentioned i-s rotated insynchronism with the conveyor C so that the cans A advanced by theturret will be properly placed on the conveyor flights I8 relative tothe locating dogs I9. For this purpose there is provided a longauxiliary drive shaft4l which extends the full length of the machine.The shaft is journaled in bearings 42, 43, 44 formed respectively on theframe extension 25, the gear casing I6, and the main frame E.

One end of the auxiliary device shaft 4| carries a bevel gear 46 whichmeshes with and is driven by a bevel gear 4.1 mounted on the main driveshaft 23. The opposite end of the auxiliary drive shaft carries a bevelgear 49 which drives a bevel gear mounted on a shaft 52 journaled in abearing formed in the gear casing I6 and in a bearing 53 formed in adifferential gear housing 54 of a differential unit 55 disposed in thegear casing.

' The inner end of the shaft 52 carries a spur gear 51 which drives apinion 58 mounted on a cross shaft 59 journaled in the differentialhousing. A second pinion 6| carried on the same shaft 59 meshes withl agear 62 mounted on a shaft 63 which is journaled in a bearing 64 of thedifferential housing 54 and in a bearing 65 in the gear casing I6.

Shaft 63 carries a bevel gear 61 which drives a bevel gear 68 mounted onone end of a shaft B9 journaled in a bearing 1I formed in the gearcasing I6. The opposite end of the shaft 69 carries a bevel gear 13which drives a bevel gear 14 mounted on the lower end of the turretshaft I4.

To insure the desired perfect timing between the can feed-in turretBrand the conveyor C there is provided a conveyor speed detectormechanism which detects and is affected by a change in the lineal speedof the conveyor as a result of a stretch or other change in its length.This detector mechanism includes a detector sprocket 11 which engages inthe links of one of the conveyor chains I1. The sprocket is locatedadjacent the turret B and is carried on a sprocket shaft 18 formed inthe main frame E, and journaled adjacent one end in a bearing 19.

The detector sprocket 11 is normally positively driven in time .withtherotation of the turret B.,

This is effected by a bevel gear 8| which is mounted on the turret shaftI4 and which drives a bevel gear 82 carried on a cross shaft 83journaled at one end in a bearing 84 formed inthe gear casing I8 and atits opposite end in a bearing formed in a detector housing 85 formed asa part of the main frame or casing E.

Inside the detector housing 89 the cross shaft 93 carries a gear 81which drives a gear 88 mounted on a shaft 89 carried in bearings 9|formed in the detector housing. The inner end of the shaft carries adriving bevel gear 93 of an auxiliary differential gear unit 94. Bevelgear 93 meshes with a pair of oppositely disposed bevel gears 95, 96mounted onshort shafts 91, 98 carried in bearings formed in an auxiliarydifferential housing 99. Bevel gears 95, 96 mesh with a bevel gear lillmounted on the detector sprocket shaft 18 and hence drives this shaft.

As long as the lineal speeds of the conveyor C and the turret B are thesame, the cans A from the turret will pass into the proper space on theconveyor C. lHowever, when an expansion or contraction `of the chains I1alter the length of the conveyor and tends to change its ,lineal speedso that the conveyor flights 8 will not properly align with the turretpocket I3, the detector mechanism comes into play. It operates throughthe differential unit 55 and through the auxiliary differential unit 94and with suitable associated electric equipment and increases ordecreases, as the case may be, the speed of the turret B and immediatelyrestores full synchronism between conveyor and turret.

For'example, where the conveyor chains I1 stretch in length, thedistances between the conveyor dogs I9 increase. For all practicalpurposes this effect is the equivalent of a reduction in the linealspeed of the conveyor. Under such conditions the detector sprocket 11,rotating with theV conveyor chains I1, slows down or rotates slower thannormal and its shaft 18 also revolves at a slower speed relative to theconstant rotation of .it-s driving shaft B9. This difference in speed`will be immediately compensated for in the auxiliary differential unitby a rotating action of the unit housing 99.

In .a similar manner, a contraction of the conveyor ychains I1 to lessthan their normal lengthI will'reduce the distance between the conveyordogs I9 and thus effectively increase their lineal speed past the'turret B. This increase in speed acts on the rotating parts of themachine in the same` manner as a decrease in speed with the exceptionlthat the auxiliary differential housing will rotate in an oppositedirection.

Rotation of the auxiliary differential unit 94 in one direction actuatesan electric switch |05 (Figs. 1 and 2) of a switch unit |06 and whenrotated in the opposite direction actuates an electric switch |01 of thesame unit. There is secured Atothe auxiliary differential housing 99 agear |09 which meshes with a gear III mounted on a switch shaft 2carried in a bearing ||3 of a bracket ||4 forme-d on a wall of thedetector casing 86 and in a bearing ||5 formed in the casing 86. Theswitch shaft carries a vertically disposed arm IIS the upper end ofwhich is normally maintained in a position midway between the electricswitches |05, |01 as shown inFigzl. Y ,Y y f y Thus when thev auxiliarydifferential housing rotates in one direction, its gear l|09 rotates thegear and hence shifts the arm ||6 into engagement with either the switch|05 or the switch |01, as .the case may be, to close a circuitconnecting therewith. When the housing rotates in the opposite direction`the arm I6 iscorrespondingly shifted to close the other one of theswitches.

These electric switches |05, |01 control the operation of a reversibleelectric motor |2| which r in turn regulates the speed of the turret Bthrough the differential unit 55.` For this purpose the motor isprovided with a rotor shaft |22 carrying .a worm |23 which meshes with aWorm wheel |24 bolted .to the housing 54 of the differential unit 55 inthe gear casing |6,

By way of example, when the electric switch is closed the motor |2| willrotate in a fdirection which will revolve the differential housing 54 todecrease the speed of the gears and shafts connecting with the turret B.This restores .the turret to full synchronism with the speed of theconveyor C. Conversely, when the speed -of the conveyor increases, theswitch |01 is closed `and thi-s rotates the motor in the oppositedirection. The differential housing 54 is therefore rotated opposite tothat just described so that the speed of the turret B will be increasedto correspond with the conveyor speed.

Referring now to the wining diagram illustrat ed in Fig. 2 it will beobserved that switch |05 is connected by a wire ||5| to a solenoid |52the opposite end of which is connected by wires |53,

|54 to a source of electric energy such as an electric generator |55.The opposite side of the generator is connected by Wires |56, |51 to theopposite side of the switch |05. Hence when switch |05 is closed, energyfrom the generator ows through and energizes the solenoid |52.

The solenoid |52 is provided with a movable core |59 having motor switchcontacts |'6|, |62 which are disposed between stationary contacts |63,|64, |65 c-onnected by respective lead wires |66, |61, |68 to thereversible motor |2|. The motor switch contacts |6| |62 are alsoconnected by respective wires |1|, |12 to the generator Wires |54, |56.

When the solenoid |52 is energized it draws in its core |59 and shiftsthe motor switch contacts |6 |62 iinto engagement with the twostationary contacts |63, |64. This completes a motor circuit connectingthe motor with the generator `and hence energy flows into the motor androtates it in a predetermined direction as hereinbefore ydescribed forbringing the speed of the turret B into synchronism with the speed ofthe conveyor C. The motor will continue to operate in this direction aslong as the yswitch |05 remain-s closed.

If a change in the lineal speed of the conveyor moves the switch arm I6away from the switch, the latter opens and breaks the solenoid circuit.This deenergizes the solenoid and hence permits the movable core toshift back into its original open position. This shift is brought aboutby pressure of the usual spring housed within the l;

solenoid. The motor switch is thus opened and the motor ceasesoperation.

The switch |01 is connected in a similar manner by a wire |8| to asolenoid |82, the opposite end of which is connected by a wire |83 tothe generator wire |54. The solenoid |82 :is disposed adjacent thesolenoid |152 and'surrounds the same movable core |59. The opposite sideof the switch |01 is connected by a-wire |85 to the generator wire |55.Hence when this switch |01 is closed by the arm ||6 the solenoid |02 isenergiized and thus draws the movable core |59 into it. This lshifts themotor switch contacts lr6 I, |62 into engagement with the two stationaryswitch contacts |64, |65.

Energy from the generator thereupon ows through the motor |2| in adirection opposite to that explained above in connection with the switch|05. Hence the motor revolves in the opposite direction. Whensynchronism is restored the switch |01 opens by a shifting of itsoperating arm` ||6 and the solenoid circuit is broken and the solenoid|82 becomes deenergized. This permits the core |59 to shift back intoits neutral original open position and open the motor switch. 'I'hemotor thereby ceases its operation in this direction.'

It is thought that the invention and many of its attendant advantageswill be understood from the foregoing description, and it will beapparent that various changes may be made in the form, construction andarrangement of the parts without-departing from the spirit and scope ofthe invention or sacricing all of its material advantages, the formhereinbefore described being merely a preferred embodiment thereof.

I claim:

l. In conveying mechanism for advancing cans and the like through atreating machine, the combination of an endless chain conveyor which issubject to change in overall dimension for carvrying cans inprocessional order through the machine, a transfer device forpositioning cans on said conveyor 'in predetermined spaced relation, andsynchronizing instrumentalities including a differential gear unitengaging and adapted to be actuated by said conveyor for increasing ordecreasing therate of operation of said transfer device in order toproperly place the cans in the predetermined spaced position on saidconveyor.

2. In conveying mechanism for advancing cans and the like through atreating machine, the combination of an endless chain conveyor which issubject to change in overall dimension for carrying cans in processionalorder through the machine, yieldable devices for keeping said conveyorchains taut, a transfer device for positioning cans on said conveyor inspaced predetermined relation, and synchronizing instrumentalities,includ-` ing a differential gear unit engaging and an electric switcharm adapted to be actuated vby said conveyor for increasing ordecreasing the rate of operation of said transfer device in order toproperly place the cans in predetermined spaced relation on saidconveyor.

3. In a conveying mechanism for advancing cans and the like through atreating machine, the combination of an endless chain conveyor which issubject to change in overall dimension for carrying cans in processionalorder through the machine, a rotatable transfer turret adjacent saidconveyor for placing cans in predetermined spaced positionsl thereon,turret driving means for rotating said turret in time with the normallinear speed of said conveyor, a rotatable detector element actuated bysaid turret driving means and engaging with said conveyor chain, anauxiliary differential unit associated with said detector element, saiddiierential unit having a normally stationary housing which is adaptedto be rotated by said detector element when said conveyor changes itsoverall dimension, and synchronizing instrumentalities set in motion bythe rotation of said differential unit housing for increasing lordecreasing the rate of rotation o1' is subject to change in overalldimension for carrying cans in processional order through the machine, adetector element operable by said conveyor when the latter changes indimension, a

rotatable transfer turret adjacent said conveyor for placing cans in-predetermined spaced positions thereon, turret driving means forrotating said turret in time with the normal linear speed of saidconveyor, a direrential unit between said turret and its driving means,said diierential unit having a rotatable but normally stationaryhousing, devices for rotating said differential unit housing, andsynchronizing instrumentalities operable by said detector element andadapted to set in motion said devices for rotating said differentialunit housing for increasing or decreasing the rate of rotation of saidtransfer turret in accordance with the change in dimension of saidconveyor in order that the cans will continue to be placed inpredetermined spaced relation on said conveyor. l

5. In conveying mechanism for advancing cans and the like through atreating machine, the combination of an endless chain conveyor which issubject to change in overall dimension for carrying cans in processionalorder through the machine, a detector element operable by said conveyorwhen the latter changes in dimension, a rotatable transfer turretadjacent said conveyor for placing cans in predetermined spacedpositions thereon, turret driving means for rotating said turret in timewith the normal linear speed of Said conveyor, a differential unitbetween said turret and its driving means, said differential unit havinga rotatable but normally stationary housing, a reversible electric motorfor rotating said differential unit housing, and electric switchinstrumentalities operable by said detector element .and adapted to setin motion said reversible elec-- tric motor for rotating saiddiierential unit housing to increase or decrease the rate of rotation ofsaid transfer turret in accordance'with the change vin dimension of saidconveyor `in order that the cans Will continue to-be placed inpredetermined spaced relation on said conveyor.`

6. In conveying mechanism for advancing cans and the `like through Vatreating machine, the

combination of an endless chain conveyor whichl is subject to change inoverall dimension for carrying cans in processional order through themachine, a detector element operable by said conveyor when the latterchanges in dimension, a rotatable transfer turret adjacent said conveyorfor placing cans in predetermined spaced positions thereon, turretdriving means for rotating said turret in time with the normal linearspeed of said conveyor, a differential unit between said turret and itsdriving means, said differential unit having a-rotatable but normallystationary housing, a reversible electric motor for rotating saidrdifferential unit housing, and electric switch instrumentalitiesoperable by said detector element in one direction when said conveyorelongates and in 'another direction when said conveyor contracts, saidinstrumentalities when operated settingl in motion said reversibleelectric motor for rotating said differential unit housing in thecorresponding direction to increase or decrease the rate of rotation ofsaid transfer turret in accordance with the change in dimension of saidconveyor in order that the c ans will continue to be placed inpredetermined spaced relation on said conveyor.

JAMES H. GORDON, IJR.

